Measured-service telephone system



J. ERICKSON.

MEASURED SERVICE TELEPHONE SYSTEM.

APPLICATION H LED SEPT- 18, 1918. 1 ,358 ,945. Patented Nov. 16, 1920.

. UNITED s'r 'rEs PATENT- omen.

JOHN ERICKSON, OF CHICAGO, ILLINOIS, ASSIGNOR T AUTOMATIC ELECTRIC COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

MEASURED-SERVICE TELEPHONE SYSTEM.

To all whom it may concern:

Be it known that I, JOHN ERIOKSON, a

citizen of the United States of America, and.

a resident of Chica o, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Measured- Service Telephone Systems, of which. the

1 following -is a specification' before a call can be completed, and one which includes means for'releasin the extended connection when the ca ed subscriber answers in case the coin has not been deposited.

These and other objects and features of my invention will be more clearly pointed out and explained in the following specification:

In the drawing I have shown only that part of an extended connection which is essential to the o erationof the coin device. The substation having a line switch of any type for selecting an idle connector switch which is in turn operated to pick out the line of a called subscriber. I have shown only the line wipers of the line switch and the line and reversing or back bridge relays of the connector. It will be understood also that selectors may be inserted between the line switch and the connector and also that said line switch and connector may be of any type in which the back bridge relay operates to reverse battery upon the response of the called subscriber.

At M, I have shown the essential parts of the coin collector in diagrammatic form associated with the line of the substation A.

When the subscriber at A removes his receiver to initiate a' call a circuit is closed from battery at the coils of the line switch over line conductor 2, springs 3, polarized relay 4, transmitter 5, receiver 6, calling -de-' vice springs C. D. springs 7 and 8 and conductor 9 back to ground and battery through the line switch. Although relay 4 is in-,

cluded in thiscircuit it does not operate, as the current now tends to draw the lower I Specification of Letters Patent.

Patented Nov. 16, 1920.

Application filed September 18, 1918. Serial N0. 254,585.

end of the armature 10 toward; the lower pole piece ofthe magnet but'is not strong enough to overcome the tension of springs 3.

The subscriber before'continuing the call must now deposit a coin in the slot of the coin box. As the coin is deposited it falls upon the upper end of a plunger 11 which is mounted in thearmature 10 of the polarized relay 4. This plunger has a spiral spring inside the armature 10 which normally tends to hold the same in its uppermost position, but WlllCh s weak enough so that the weight of the com on the upper end is strong enough to compress the spring and force the plunger to its lowest position as shown in the drawing.

The plunger when thus presseddown, op-

erates to close the springs 12 at the lower end thereof, and removes the catch 13 from engagement with the arm 14. The subscriber may then proceed to dial the wanted number by means of the calling device C. D. during which operation, the polarized relay 4 and the transmitter and receiver are short circuited by means of the shunt springs 15 to prevent annoyance to the subscriber or I false operation of the polarized relay. When the receiver was first removed the line switch (I, only the wipers of which are shown, operated to automatically extend the connection to an idle one of a plurality of connector switches H. The operation of the calling device now controls the line relay 16 of theconnector Hto bring the wipers of said switch into connection with the desired subscribers line in the usual manner, whereupon the said connector operates to project signaling current over the called subscribers line to signal the subscriber. As soon as the subscriber at B lifts his receiver in response to this signal, a circuit is closed for the back vbridge relay 17 in series with the called line and battery. Relay 17 energizes and reverses the connections of the windings of the line relay 16 with regard to the line conductors leading to the calling station, thereby. reversing the flow of current in the calling subscribers line circuitand through the polarized relay 4. This reversal of current through relay 4 causes relay 4 to attract the upper end of armature 10 to the upper pole piece of said relay, thereby removing the upper end of the plunger to the right and allowing the coin to pass down the left hand chute and be collected. A further result of the attraction of this armature is the closing of the springs 18 by means of the part 19, and the resultant short circuiting of the polarized relay 4.

Conversation may now proceed over the heavy conductors shown, and after conversation is completed the switches are restored and the connection released in the usual manner by the restoration of the receiver of the 1 calling subscriber to the switchhook. As the hook is restored, the springs 8 and 20 are brought into-contact, therebyclosing a circuit which was prepared by the springs 12 when the coin was inserted. The closure of this circuit in series with the line circuit and battery passes through said springs 8 and 20 magnet 21, springs 12, and conductor 2 to the other side of battery at the line switch. The magnet 21 being of high resistance alone energizes over this circuit and operates to attract its armature 22 to rotate the arm 23 about its axis and also to close the springs 3 in case they had been operated. The rotation of arm 23 operates, through the medium of the link 25 to again draw the armature 10' and its plunger, back to normal position, thereby causing arm 19 to pass out from under the springs 18, openin the same, and also when arm 19 disengages springs 18, the plunger 11 moves back to its uppermost position and opens the springs 12 in the circuit of the release magnet'21.

Now assume that the subscriber at A attempts to set up a call without first depositing a coin in the slot. In this case the operation will proceed as usual except that arm 13 will not be removed from under arm 14 due to the fact that the plunger 11 of the coin collector has not been forced downward by a coin. Therefore when the called subscriber answers the call and battery is reversed by relay 17 of the connector, the relay 4 will attract its armature as before toward the upper pole piece, but will in this case also draw the arm 14 up by means of part 13 and thereby cause springs 3, which have been held together, to open their contact. The opening of springs 3 opens the line circuit to the automatic switches and causes the release of the connection in the same manner as when the receiver is recalled subscriber, and one which releasesan entire connection when the called man answers, in case thecoin is not first deposited! Having fully described, and ascertained the features and aspects of'my invention,

What I consider to be new and desire to have protected by Letters Patent will be out in-the appended claims.

What I claim as my invention is:

1. In a telephone system, a pair of lines, means for establishing a connection between said lines, a coin collector for the calling line, means controlled by the response of'the called subscriber for collecting a coin when deposited in. said collector and for releasing the entire connection if the coin is not deposited.

2. In a telephone system, a pair of lines, a pluralityof automatic switches for establishing a connection between said lines, a coin collecting device for the calling line, means controlled by the response of the called subscriber for collecting a coin when deposited before the call, and for releasing all of said switches if the coin is not deposited.

3. In a telephone system, a pair of lines, means for establishing a talking circuit between said lines, a coin collecting device for the calling line, means controlled by the subscriber on the called line for collecting a previously deposited coin in said device, and for opening said talking circuit to release the connection between said lines if a coin is not previously deposited.

4. In a telephone system, a pair of lines, means for establishing a talking circuit between said lines, a coin collecting device for the calling line, means controlled by the subscriber on the called line for collecting a previously deposited coin in said device, and for opening said talking circuit to release the connection between said lines if a coin is not previously deposited, and means controlled by the restoration of the receiver at the calling substation for again closing said talking circuit. 1

5. In a telephone system, a pair of lines, means for establishing a talking circuit be tween said lines, a coin collecting device for the calling line, means controlled by the subscriber on the called line for collecting a previously deposited coin in said device, and for opening said talking circuit to release the established connection if a coin is not previously deposited, and means controlled by the restoration of the receiver at the calling substation for again closing said talking circuit.

6. In a telephone system, a pair of lines, means for establishing a connection between said lines, a coin collecting device for the calling line, a relay in said device, means controlled by the response of the called subscriber for operating said relay to collect a pointed previously deposited coin, and for operating said relay to release said connection when a coin is not deposited.

7. In a telephone system, a magnet, an armature for said magnet, a movable plunger in said armature, a pair of springs operated by said plunger independent of said magnet, another pair of springs always operated by said plunger when the magnet is energized, and another pair of springs operated by said plunger when the magnet is energized only in a certain position of said plunger.

8. In a coin collecting device, a magnet for controlling the collection of a coin, an armature for the magnet, a movable plunger mounted in said armature and adapted to be controlled by the depositing of a coin, a circuit controlling said plunger when a coin is deposited, another circuit controlled b said plunger when the magnet is energize and another circuit controlled by said plunger only when a coin is deposited and the magnet is energized.

9. In a telephone system, a coin collecting I for again closing said device, a magnet for controlling the collection of a coin, an armature for said magnet, a plurality of contacts controlled by said armature, said armature normally operative to operate all of said contacts when the magnet is energized, and inoperative to operate certain of said contacts if a coin is deposited in the device.

10. In a telephone system, a pair of lines, means for establishing a talking circuit between said lines, a coin collecting device for the calling line, a magnet for controlling the operation of said device, means controlled by the removal of the receiver at the called substation to energize said magnet to collect the coin, and means controlled by the energization of said magnet for opening the talking circuit to release the connection if the coin is not deposited and a second magnet controlled by the calling subscriber talking clrcuit.

Signed by me at Chicago, Cook county,

Illinois, this 11th day of September, 1918.

JOHN ERICKSON. 

